In a bed apparatus, the bottom on which a mattress is placed is formed of approximately rectangular, molded metallic plates being arrayed in the longitudinal direction of the bed apparatus. In order to support back-raising and foot-raising operations, the bottom is composed of the aforementioned rectangular plates with their short side arranged in the length direction of the bed apparatus (see Japanese Patent Application Laid-open 2006-198352 (Patent Document 1)).
In the bed apparatus of this kind, a plurality of plates are joined and placed on the bed frame. Because the joined plates flex in back-raising and/or leg-raising operations, the plates need to be arranged with gaps therebetween.
However, there is a fear that the gaps between plates causes the user to feel a jagged sensation. Though the user's feel of a bed can be bettered by the mattress, there has been no proposal of the bottom that can prevent this jagged sensation.
Further, as a structure for preventing the mattress from slipping sidewards over the bottom, in Patent Document 1, a pair of anti-sideslip members are arranged along both sides of the bottom. The anti-sideslip members engage the edges of the mattress to prevent slip.